K. Ichizuka et al., The effect of cytokines on parathyroid hormone-related protein (PTH-rP) production in human amnion cells, ENDOCR J, 46(4), 1999, pp. 479-486
In the present study, the effects of various cytokines on parathyroid hormo
ne-related protein (PTH-rP) production and PTH-rP mRNA expression in human
amnion cells were studied. Immunoreactive (ir) PTH-rP was measured by immun
oradiometric assay and the expression of PTH-rP mRNA was determined by Nort
hern blot analysis. The addition of interleukin-1 beta (IL-1 beta, 10 ng/ml
) and IL-6 (10 ng/ml) in culture medium for 24 hours resulted in a signific
ant increase in ir-PTH-rP levels by 1.5 and 1.6 fold, respectively. The eff
ects of these agents were dose dependent. In contrast, IL-2 (10 ng/ml) and
IL-8 (10 ng/ml) showed no effect on the production of ir-PTH-rP from amnion
cells. Treatment with IL-1 beta or IL-6 for 6 hours increased the expressi
on of PTH-rP mRNA in amnion cells. The stimulatory effect of IL-1 beta was
reduced by IL-1 receptor antagonist (IL-1Ra) in a dose dependent manner. Bo
th tetradecanoyl phorbol acetate (TPA), and forskolin increased PTH-rP mRNA
levels and the PTH-rP production in amnion cells, and the effect of TPA wa
s much greater than that of forskolin. The findings of the present study su
ggest of the participation of inflammatory cytokines for the regulation of
PTH-rP production in human amnion cells.